Marine Weather and Tide Forecast for Rosedale, WA

SYNOPSIS
Elevated river runoff conditions will continue with significant river flooding impacts for many areas. Saturday will see much needed drier weather ahead of a weak frontal system Saturday night into Sunday. A stronger system will follow Monday into Tuesday with heavier precipitation and potentially windy conditions for some areas. There is potential for heavy mountain snow Tuesday and Wednesday.



SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/
High pressure is giving us a brief respite from the wet and active weather this week. That being said, there are still numerous rivers within flood stage with associated impacts. While some rivers have crested and are receding, we are still seeing new floods based on dam releases.

Rain chances increase again moving into Sunday as the ridge flattens. Snow levels remain high, over 6,000 ft, with lowland totals generally under 0.10" and 0.25" or less in the mountains.
These totals are not hydrologically significant, though.
However, precip coverage and rates will be increasing moving into Sunday night and Monday. 33

LONG TERM /MONDAY THROUGH FRIDAY/
The next AR event, slated for Sunday night and Monday, brings another round of heavier precipitation to western Washington. Interior lowland areas may see an additional 0.50-1.00" of rain, with 1-2" over the coast and 1-3" (with locally higher amounts) in the mountains. These totals may prolong river flooding and/or renew flooding for a few rivers across the region. However, we are not anticipating widespread major flooding as we've just seen. It'll be windy as well with widespread south wind gusts to 30-40 mph. We stay in a moist/wet pattern moving into Tuesday and Wednesday, but by then the snow levels will be lowering to around 4000 ft (Tue)
and 2500 ft (Wed) with the focus turning toward heavy snow in the Cascades and passes. Total snow amounts in the mountains remain high moving toward the end of the week as snow levels remain low. 33

AVIATION
Northwesterly flow aloft remains in place while most terminals are reporting southeasterly winds generally 4 to 8 kts. Cigs remain mixed over W WA this evening with IFR to LIFR present along the coast as well as some of the San Juan islands. The terminals around the Sound show a mix of VFR to MVFR conditions as cigs lift and drop from time to time. Widespread IFR conditions expected to emerge tonight and remain largely in place into early Saturday afternoon. Isolated locations may only lower to MVFR conditions, but these will likely be the exception and not the norm. Given abundant low level moisture, vis reductions overnight are also expected to be an issue with terminals seeing at least some impedance...although most will see vis as low as 1/2SM at some point overnight and Saturday morning. Improvement into VFR expected after 20Z for the majority of terminals.

KSEA...Cigs continue to oscillate between IFR and VFR depending on consistency of the lower stratus deck. While this may continue to bob up and down in the evening hours, after 06Z tonight more consistent IFR conditions are expected. Limited visibility will also be an issue as latest guidance suggests a 20-25% chance of seeing visibility below 1SM between 12Z-18Z. Improvement into VFR expected after 19Z-20Z. South to southeasterly winds expected for much of the TAF period with speeds generally 4-8 kts.

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MARINE
A series of weather systems are expected to move through area waters starting this weekend and continuing into next week. A weak system is expected to move over area waters on Saturday into Sunday morning. There is high confidence (70-90%) that this system will bring gusts meeting small craft advisory thresholds for the coastal waters as the front pushes through. The next system arrives Sunday night continuing into Monday. This system will be much stronger and bring elevated seas and winds. Latest guidance suggest there is high confidence (70-100%) for winds meeting small craft thresholds. There is also moderate confidence (50-70%) for gale gusts over the coastal waters. Seas will build to 13-19 ft for the coastal waters. Seas will decrease slightly Tuesday morning, but still hover between 10- 13 ft. Another system on Tuesday will bring impactful weather to area waters. Latest guidance suggests another round of small craft winds (50-90%) chance, with highest probabilities over the coastal waters and western Strait. Seas will build again to 14-17 ft.

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HYDROLOGY
Key messages below.

* Numerous River Flood Warnings remain in effect across western Washington, with varying times and flood levels.

* A Flash Flood Watch remains in effect for a potential levee failure of the Skagit River below Sedro-Wooley to the mouth of the Skagit River through late Friday.

* More wet weather early next week with potential for renewed flooding.

With very wet antecedent soil conditions, the landslide threat across the region has increased with this system, and several landslides and mudslides have already occurred in steep terrain across western Washington. Potential has also increased for debris flows over area burn scars, which continue to be monitored.

While the threat of urban flooding has decreased, the threat of small stream flooding, as well as for areas with poor drainage, continues to pose a risk of localized nuisance flooding and ponding on roadways. Low water crossings may become impacted or impassable.

The latest river observations and forecasts can be found at water.noaa.gov.

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SEW WATCHES/WARNINGS/ADVISORIES
WA...None.
PZ...Small Craft Advisory from 4 PM Saturday to 1 PM PST Sunday for Coastal Waters From Cape Flattery To James Island 10 To 60 Nm-Coastal Waters From Cape Flattery To James Island Out 10 Nm-Coastal Waters From James Island To Point Grenville 10 To 60 Nm-Coastal Waters From James Island To Point Grenville Out 10 Nm-Coastal Waters From Point Grenville To Cape Shoalwater 10 To 60 Nm-Coastal Waters From Point Grenville To Cape Shoalwater Out 10 Nm.